Compilare: user.c: In function ‘createNode’: user.c:16:2: warning: implicit declaration of function ‘malloc’ [-Wimplicit-function-declaration] Node *x = (Node*)malloc(sizeof(Node)); ^ user.c:16:19: warning: incompatible implicit declaration of built-in function ‘malloc’ [enabled by default] Node *x = (Node*)malloc(sizeof(Node)); ^ user.c: At top level: user.c:46:1: warning: return type defaults to ‘int’ [enabled by default] listDisplayS(List l) { ^ user.c:56:1: warning: return type defaults to ‘int’ [enabled by default] listDisplayE(List l) { ^ user.c: In function ‘listDisplayS’: user.c:54:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘listDisplayE’: user.c:64:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘main’: user.c:77:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &n, &c); ^ user.c:79:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &aux); ^ user.c:85:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &aux); ^ user.c:89:10: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &aux); ^